Project Summary/Abstract: The objective of this proposal is to create a new low-cost, disposable system that enables reliable, safe, standard endoscopes to replace expensive, customized duodenoscopes, which have recently been shown to cause infections at an alarming rate. Clinical signi?cance comes from the fact that 40,000 patients per year will be infected by unclean duodeno- scopes, among the 700,000/year who undergo endoscopic retrograde cholangiopancreatography (ERCP) in the USA alone. The reason for this is that duodenoscopes contain tiny moving parts, used to aim transendoscopic tools sideways at the endoscope tip, which harbor bacteria. In response to the alarming infection rates, in August 2019 the FDA issued a call-to-action for medical device manufactures to develop novel, disposable devices for ERCP, and for hospitals to rapidly adopt them once available. Our Innovation is to enable ERCP by augmenting a standard endoscope with a novel low-cost disposable steerable sheath/endcap system. Our innovative steerable sheath (which passes through the endoscope port) uses stiffness asymmetry in two thin-walled tubes to enable steering of trans-endoscopic instruments carried in its large central lumen. The tubes are attached at their tips, enabling the stiffness asymmetry to transform small axial tube motions into dexterous local bending at the endoscope tip. The result is an inexpensive, disposable device for dexterously steering the ?exible guidewires, cannulas, and sphincterotomes used in ERCP. At the endoscope tip, the sheath passes through a curved channel built into a custom endcap that (1) aims it sideways and (2) provides side-view-visualization via an integrated mirror. Our approach in Aim 1 is to design a clinically-ready version of our steerable sheath/cap system by optimizing tube mechanical properties while designing for scalable manufacturing. Aim 2 focuses on designing the end cap for optimal tool delivery and side-view mirror-based visualization. Aim 3 focuses on statistically powered experiments to compare our new device to standard duodenoscopes in terms of papilla cannulation rate, can- nulation time, and navigation time to the duodenum, and an animal pilot study to demonstrate in vivo usability. Success in these aims will strongly motivate the Phase III activities described in the Commercialization Strategy document (supported by private capital after the conclusion of this Phase II SBIR) where we complete the FDA 510(k) clearance process, and release our device to the commercial market.